• 한국동물학회지
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• 제3권1호
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• pp.19-23
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• 1960

A method for determination of thyroid secretion rate in rabbit by means of radioactive iodine presented. After injection of radioactive iodine, in vivo determination so f radioactivity in thyroid gland were made during a 19 day-experimental period. In the same period blood samples were drawn and analyzed for protein-bound iodine (PBI) and for protein-bound radioactive iodine(PBI181). A rate constant for secretion of thyroid hormone was calculated from the disappearance rate of radioactive iodine in thyroid gland. The secretion rate of radioactive hormone iodine was calculated by multiplying this rate constant by the amount of radioactive iodine present in thyroid gland. Assuming that the specific radioactiveness of the circulating thyroid hormone and of the hormone just secreted were identical , thyroid secretion rate was calculated by the equation. {{{{ { Secreted hormone-iodine , gamma /hr} over { Secreted hormone-I^131, % dose/hr }= { PBI, ${\gamma}$/ml.Serum} over { PBI^131 , % dose/ml . Serum } }} The method presented consisted of measurements for series of independent criteria on thyroid function, and the resulting thyroid secretion rate was calculated by combination of those.

• 한국수정란이식학회지
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• 제13권2호
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• pp.97-106
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• 1998

The pronuclear injection of metallothionein-human growth hormone (MT-hGH) gene into rabbit zygotes was performed to establish in vitro developmental system and to detect the presence of the injected gene by nested PCR. Mature female New Zealand White rabbits were superovulated by eGG and hCG treatments. The rabbits were mated and the zygotes were collected from the oviducts 18-22 h after hCG injection by flushing with D-PBS. Two to three picoliters of MT-hGH gene was microinjected into male pronuclei. The foreign gene-injected zygotes were cultured in TCM-199 or RD mediurn containing 10% FCS with a monolayer of rabbit oviductal epithelial cefls in a 5% $CO_2$ incubator. The presence of injected DNA in rabbit embryos or blastomeres at different developmental stages .vas detected by a nested PCR analysis. The results are summarized as follows ; 1.The developmental rate of the MT-hGH gene-injected zygotes to blastocyst was significantly higher in TCM-199 medium (68.1%) than in RD medium (42.9%). 2.The gene injection into pronuclei at 18 or 22 hours post hCG treatment during pronuclear stage did not much affect on the in vitro development of the rabbit embryos. 3.The rate of gene-positive embryos detected by the nested PCR analysis was significantly decreased when they developed to blastocysts. The results indicate that the screening of transgene in rabbit embryos by nested PCR analysis could be a prornisible method for the preselection of transgenic embryos. Furthermore, the preselection of transgenic embryos would greatly reduce hoth the cost and effort of production of transgenic animals.

• 한국가축번식학회지
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• 제21권4호
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• pp.363-371
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• 1997

The present study was carried out to investigate the effect of gonadotropin administration on blood ovarian steroid hormone in angora rabbit. Mature angora rabbits were primed for superovulation with PMSG 100IU. Eighty hours later, the rabbit were induced to ovulate with HCG 100IU. In exp 1, blood progesterone and estradiol of superovulated does were measured by radiommunoassay. Blood progesterone concentration at 93, 99, 102 and 114 hours after HCG injection were 12.9$\pm$0.5, 34.8$\pm$5.1, 12.2$\pm$2.7 and 43.4$\pm$5.8ng/ml, respectively. Mean progesterone concentration of blood collected at 99 and 114 hours after HCG injection(p<0.05). However, mean blood estradiol concentration was not changed. In exp 2, superovulated does were unilaterally ovariectomized at 96 hours after HCG injection. Blood progesterone concentration was tend to be decreased after ovariectomy. Nosignificant changes in blood estradiol concentration was observed after ovariectomy. In exp 3, superovulated does were bilaterally ovariectomized at 96 hours after HCG injection Ovariectomized does were treated with progesterone. Blood progesterone level in the rabbits treated, twice daily, with 5mg progesterone after ovariectomy was similiar to that in the superovulated intact rabbits. Blood estradiol concentration of the rabbits after bilateral ovariectomy was beyond detection range. Blood progesterone concentration was significantly decreased to 7.6$\pm$3.0ng/ml wi thin 3 hours after ovriectomy(p<0.05). However, that value was increased to 34.8$\pm$8.2ng/ml by 5 mg progesterone treatment and this elevated level was significatnly decreased to 7.3$\pm$2.4ng/ml at 12 hours after progesterone administration(p<0.05).

• Journal of Animal Science and Technology
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• 제64권3호
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• pp.432-442
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• 2022

The purpose of this study was to analyse the effects of light colour on rabbit reproductive performance and the expression of key follicular development genes. Rabbits (n = 1,068, 5 months old, 3.6-4.4 kg live body weight) were divided randomly into four groups, housed individually in wire mesh cages and exposed to red, green, blue, and white light-emitting diode (LED) light (control). The lighting schedule was 16 L : 8 D-15 d / 150 lx / 6:00 am-22:00 pm (3 d preartificial insemination to 12 d postartificial insemination). Red light and white light affected the conception rate and kindling rate and increased the total litter size at birth (p < 0.05). The effects of red light on litter size at weaning, litter weight at weaning, and individual weight at weaning increased compared with the green and blue groups. The effects of red light on live litter size at birth were increased compared with those in the blue group (p < 0.05). Compared to white light, green and blue light reduced the number of secondary follicles (p < 0.05). Compared to red light, green and blue light reduced the number of tertiary follicles (p < 0.05). Compared with white light, red LED light resulted in greater ovarian follicle stimulating hormone receptor and luteinizing hormone receptor mRNA expression (p < 0.05). Compared with green and blue LED light, red LED light resulted in greater B-cell lymphom-2 mRNA expression (p < 0.05). Compared with green LED light, red LED light inhibited FOXO1 mRNA expression in rabbit ovaries (p < 0.05). Red light can affect the reproductive performance of female rabbits and the expression of key genes for follicular development.

• The Korean Journal of Physiology
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• 제26권2호
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• pp.99-111
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• 1992

Permissive action of thyroid hormone at the level of Ca channel and responsible mechanisms underlying thyroid hormone-induced change in myocardial contractile state and $T_3-induced$ arrhythmias were investigated in rabbit ventricular or atrial myocytes using whole cell patch clamp technique. Single cells were isolated by Langendorff perfusion with collagenase. Cardiac myocytes were incubated in $low-Cl^-,$, $high-K^+$ medium containing $1_{\mu}M\;L-triiodothyronine\;(T_3)$ at $4^{\circ}C$ for 2.10 hours. The calcium currrent $(I_{Ca})$ was increased in $T_3$ loaded cells, however, the shape of current voltage curve and reverse potential did not altered. Cyclic AMP, cyclic GMP, isoprenaline and 3-isobutyl-1-methyl-xanthine increased $I_{Ca}$ in euthyroid and hyperthyroid conditions, and acetylcholine blocked the increase of $I_{Ca}\;in\;T_3$ loaded cells. The amplitude of $I_{Ca}$ was much larger after perfusing cGMP than cGMP in both conditions, whereas the degree of increase of $I_{Ca}$ was greater after perfusing cAMP than cGMP in $T_3$ loaded cells. The degree of increase of $I_{Ca}$ after perfusing isoprenaline or IBMX also was greater in $T_3$ loaded cells than in control cells. Background current induced by isoprenaline also increased in $T_3$ loaded cells. The Ca release dependent inward current was increased in amplitude but its activation and inactivation time course was not changed in $T_3$ loaded cells. Activation of Na pump current was not changed in $T_3$ loaded cells. From the above results it is suggested that thyroid hormone induced increase in the contractile state of cardiac myocytes are accompanied by augmented $I_{Ca}$ and the increase of Ca release from sarcoplasmic reticulum and the permissive action of thyroid hormone to catecholamines could induce arrhythmias through the increase of $I_{Ca}$ and background current.

• 약학회지
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• 제38권4호
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• pp.440-450
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• 1994

Due to the limited bioavailability of $[D-Ala^6]$LHRH from nonparenteral transmucosal sites of administration, enhancement of mucosal permeability by coadministration of several protease inhibitors and/or penetration enhancers were studied in rabbit mucosa. As a reliable bioassay method for $[D-Ala^6]$LHRH, ovulation-inducing effect were measured after vaginal administration in the rat. The permeation of $[D-Ala^6]$LHRH through the mucosal membrane of rabbit mounted on George-Grass diffusion cells were examined in the presence of polyoxyethylene 9-lauryl ether (POE), ${\beta}$-cyclodextrin$({\beta}-CyD)$ or ethylene diamine tetra acetate disodium salt(EDTA). The vaginal membrane showed higher permeability of $[D-Ala^6]$LHRH than the rectal and nasal membrane. POE and ${\beta}-CyD$ showed a small promoting effect on the membrane permeation of $[D-Ala^6]$LHRH, but EDTA showed significant enhancement. Ovaluation was enhanced by the coadministration of sodium laurate(0.5%), a protease inhibitor but was not enhanced by EDTA, a penetration enhancer. On the other hands, coadministration of sodium tauro 24,25 dihydrofusidate(1%) and EDTA(2%) enhanced the ovulation inducing-effect 2.8 times. These results suggest that the vaginal administration of $[D-Ala^6]$LHRH with STDHF or sodium laurate as a protease inhibitor, and EDTA as a penetration enhancer, may become an elective method for transmucosal delivery of $[D-Ala^6]$ LHRH.

• 대한수의학회지
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• 제27권1호
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• pp.27-34
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• 1987

To verify the direct effects of the thyroid hormone ($T_3$) on the rabbit heart, $T_3$-Tyrode solution in vitro was perfused on the normal atrial muscles and enzymatically isolated ventricular myocytes of the rabbit. All the experimental procedures were conducted at $35^{\circ}C$ and the same procedures were repeated after Ca. 120 minutes from the beginning of $T_3$-Tyrode perfusion. Compared to the state between the normal Tyrode solution and $T_3$-Tyrode solution, results were observed on the same cells by electrophysiological methods (conventional intracellular recording and whole cell patch clamping) as soon as possible. The results obtained were as follows : 1. Action potential duration (APD) on the left atrial muscle was reduced under the perfusion of $T_3$-Tyrode. 2. Absolute refractory Period was shortened by $T_3$-Tryrode perfusion. (117 msec./114 msec., 90 msec./78 msec.) 3. Maximal Ca currents ($i_{Ca}$) were decreased in single: ventricular myocytes under the $T_3$-Tyrode (2.98 nA) than under the normal Tyrode (6.65 nA) 4. On I-V relation, reversal potential was shifted to lower membrane potential and membrane potential showing maximal $i_{Ca}$was lowered from +10mV to -20mV by $T_3$ effect. 5. Above results were likely to explain that tachycardia in the hyperthyroid state was caused in part by the reduced repolarization phase and the reduced refractory period due to the decrease of the Ca current.

• Animal Bioscience
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• 제35권9호
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• pp.1444-1453
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• 2022

Objective: Acetate plays an important role in host lipid metabolism. However, the network of acetate-regulated lipid metabolism remains unclear. Previous studies show that mitogen-activated protein kinases (MAPKs) and mechanistic target of rapamycin (mTOR) play a crucial role in lipid metabolism. We hypothesize that acetate could affect MAPKs and/or mTOR signaling and then regulate lipid metabolism. The present study investigated whether any cross talk occurs among MAPKs, mTOR and acetate in regulating lipid metabolism. Methods: The ceramide C6 (an extracellular signaling-regulated kinases 1 and 2 [ERK1/2] activator) and MHY1485 (a mTOR activator) were used to treat rabbit adipose-derived stem cells (ADSCs) with or without acetate, respectively. Results: It indicated that acetate (9 mM) treatment for 48 h decreased the lipid deposition in rabbit ADSCs. Acetate treatment decreased significantly phosphorylated protein levels of ERK1/2 and mTOR but significantly increased mRNA level of hormone-sensitive lipase (HSL). Acetate treatment did not significantly alter the phosphorylated protein level of p38 MAPK and c-Jun aminoterminal kinase (JNK). Activation of ERK1/2 and mTOR by respective addition in media with ceramide C6 and MHY1485 significantly attenuated decreased lipid deposition and increased HSL expression caused by acetate. Conclusion: Our results suggest that ERK1/2 and mTOR signaling pathways are associated with acetate regulated HSL gene expression and lipid deposition.

• 한국수산과학회지
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• 제33권1호
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• pp.55-59
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• 2000

무지개 송어의 뇌하수체 및 배양액에 존재하는 GTH II 농도를 측정하기 위해 Avidin- Biotin complex를 이용한 sandwich EIA 계을 개발했다. Protein A sepharose affinity chromatography을 통해서 얻어진 연어 GTH II의 rabbit IgG에 biotinylation시킨 것 (Biotin-salmon GTH II rabbit IgG)을 제2 항체로 사용하였고, Non-Biotin salmon GTH II rabbit IgG는 단지 protein A sepharose affinity chromatography에서 얻어진 IgG를 제 1 항체로 사용하였다. EIA는 sandwich법에 의해서 이루어졌으며, 효소반응 기질로는 TMB(3,3'5,5-tetramethylbenzidine)를 이용했으며, 반응후 450 nm의 흡광도에서 automatic microplate reader로 측정하였다. 그 결과, $0.12\;{\~}\;125\;ng/ml$의 범위에서 용량반응곡선을 얻었으며, 측정감도 (최소 검출량)는 거의 0.58 ng/ml 정도 였다. 그리고 뇌하수체 추출물 및 배양액 각각의 희석곡선은 GTH II 표존곡선과 일치 하였다. 또한 이러한 GTH II의 표준곡선는 뇌하수체내 다른 peptide hormone와는 교차반응을 거의 나타내지 않았다. Testosterone을 처리한 미성숙 무지개 송어의 뇌하수체 세포배양계를 이용하여 sGnRH에 의한 GTH II 분비량을 본 sandwich EIA계와 RIA계를 비교 조사한 결과, 거의 같은 분비량을 나타냈을 뿐만아니라 같은 분비 pattern을 나타냈다. 이러한 결과로부터 본 sandwich법 EIA계에 의해서 연어과 어류의 뇌하수체 추출물 및 뇌하수체 배양액 중의 GTH II 함량 및 분비량을 측정하는데 있어서 안정된 assay계라고 생각되어진다.

• 약학회지
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• 제38권5호
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• pp.602-607
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• 1994

Based upon the previous experiments showing that kidney and lung tissues of rat had relatively abundant bradykinin binding sites, we tried to characterize and determine the densities of the bradykinin binding sites in the rabbit kidney tissue and proximal tubular cells under different growing conditions. Among the kidney tissue renal medulla segments showed the highest bradykinin binding sites. To determine which growth factors are to add in the serum free culture medium to express selectively the bradykinin binding sites in the rabbit kidney proximal tubular cells, we tried so called hormone-deletion approach and in here insulin, hydrocortisone, transferrin, triiodothyronine and prostaglandin $E_1$ are examined. By performing receptor binding assay and determination of protein concentrations, we may conclude that the most required hormones in the expression for bradykinin binding sites are insulin and transferrin, and fetal bovine serum is shown to be less effective in this regard.